JiuWeiYaoHo的博客

列表推导式Buy = [{oranges,4},{newspaper,1},{apples,10},{pears,6},{milk,3}].1 ->[{Name,2*Number}||{Name,Number} <- Buy].<- [{oranges,8},{newspaper,2},{apples,20},{pears,12},{milk,6}]2 ->[{2*Number}||{Name,Number} <- Buy].<-[{8},{2},{20},{